point-to-polygon

To transform our geometric data to GRASS
i am looking for an algorithm to find a point
for an area polygon which is definitly inside the polygon.

I'ts a kind of point-in-polygon question, but i have
the polygon not the point.

r.r.

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   Rolf Rissiek | Freie Universitaet Berlin
   rolft2@sonne.zedat.fu-berlin.de | Fachrichtung Kartographie
   phone +49 30 838-6352 | Arno-Holz-Str. 12
   fax +49 30 838-4842 | D-1000 Berlin 41